How-to apply 3P3R robots

This page introduces how to apply 3P3R robot. 

Step-by-step guide

1. Download the build supporting 3P3R robot from robotmaster website. The build number is: Robotmaster_V6.1.4058.
2. Set Robx file:
   1. The robot architecture type in Robx file must be set to "DECOUPLED_3P3R".
   2. Set DH chart. 
      1. The first three links are set basing on the wrist centre position as all the joint value are in zero;
      2. If there is translation joint holding part, the translation direction in DH chart must be reversing with the direction in real robot. For example, if Joint 2 positive direction in real robot is along +Y of world frame, it must be set to -Y in DH chart.
   3. Add the joints holding part to <tempVariables>.  For example, if second joint of robot holds part, it would be set as: 
      
   4. Set robot base frame which has Z axis collinear with translation direction of first joint.
   5. Joint motion range and other setting are same as other decoupled robot;
3. Set Simulation XML file.
   1. Place the joint holding part to part chain.
   2. If robot STL models are created from posture with no zero value, an extra transformation must be added in. For example,  theSTL models in attached folder KMC3P3R.zip,  are created when A3 is -700,  transformation matrix <J3_transform> is inserted for moving Joint3, joint4, joint5, joint6 up 700, which is the correct position when A3 is zero. In this case, another extra transformation, which is the inverse of <J3_transform>, was added in before <Holder_transform>, because holder and spindle transforms should not be affected by <J3_transform>.

Two 3P3R robots have been set up and are attached in here:

RM_CELL_E1_E2_E3_Wrist_TOOL-PART.zip

KMC3P3R.zip

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